Answer:
Number one and two
Explanation:
In sentence one, subject (many small retailer) agrees with verb (boost) and in sentence two, subject (the receptionists) agrees with verb (are). But the sentence three, subject (team projects) does not agree with the verb (is) and in sentence four, the subject (the performance review) also does not agree with verb (are). Hence, sentence number one and two have correct subject-verb agreement.